sorry, lost track of this thread, it can get confusing keeping track of the many fields and teams websites and PBNation forums. Any way, I was useing a 12 gram powered LAW and I see you are looking for one that doesn't need those ...so am I. I want to use a remote line for my marker and the LAW, Maybe use a quick release to switch between the two. The 12 grams are a pain and can get expensive at HEP as you have to shoot those damm tanks every 5 mins==lots of 12grams===$$. If one of us finds a good plan PM the other.

20 inches, 6 pounds and all metal except the PVC barrel, auto recharging via remote hose and HPA tank. 190 fps Nerf. Gets an aimed shot off every 4-6 seconds. Hangs on your side. You can crawl with it and hold your own in a firefight with your marker.

Close up of the plumbing and hardware. You can see where the HPA remote hose goes direct into the reg.

Then there is this goodie invented by Fastlearner:

Very compact and can generate a 230 fps nerf in that incredibly short barrel. Uses that plumbing Union fitting as a burst disk type valve. The number of sheets of household aluminum foil controls the velocity. Just activates the 12 gram, it builds pressure and Boom! My tank is dead...

Jvtech, what is that u shaped piece on the back of your launcher that connects the solenoid to the barrel. I thought about a design very similar to yours.

It's two 90 degree PVC fittings that had Male to Female threads with a Close Nipple Steel pipe fitting to join them together. Works great cause if you need a little more room you replace the nipple pipe fitting with a longer Metal pipe.